Art of preparing sheet gelatin material



April 27 1926. 1,582,605 7 w. HOSKINS ART OF PREPARING SHEET GELATIN MATERIAL Filed May 22, 1922 IWUJYW:

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UNITED sures WILLIAM HOSKINS, OF CHICAGO, J ILLINOIS.

" ART or PREPARING SHEET GELATIN MATERIAIL.

Application filed Ma 22,

To all whom it may concern:

Be it'known that I, WILLIAM HOSKINS, a citizen of the United States, residing at Chica 0, in the county of Cook and State of Illinois, have inventeda 'new and useful Improvement in Art of Preparing Sheet GelatinMaterial, of which the following is -a specification. v

The present invention relates to the art of preparing sheet elatin material and more articularly continuous sheets of very thin, ardened gelatin, particularly suitable as a wrapping'for food products, color filters,

Attempts have hitherto been made to produce sheets and films. of gelatin material, both hardened and unhardened, bymeans of a flexible base of metallic material, such as zinc, iron, and the like. It has been found,

however, that such materials can be used only for short periods as they rapidly acquire surface characterlstics resulting in imperfect film formation, which may be due either to imperfect adhesion during the formation of the film or to too great adhesion during the stripping of the film, in blemishes in the film'due to the corrosion of "spots 'on the surface of the base, and -in many other defects. In carrying out the present invention, these disadvantages are overcome, and other advantages are gained, as will be apparent from the following description of the invention, illustrated by the accompanying drawings, in which: Figure lisa diagrammatic view of apparatus suitable for carrying out the invention. A a e Referring more particularly to the drawtings, the numeral 5 indicates the film-form- Za o ing base, which is preferably flexible and may suitably be fed from the roll 6. The film-forming base is of impressionable, nonmetallic material, preferably of a cellulose nitrate plastic (such as celluloid), a cellus to lose acetate plastic, or a plastic of other suitable cellulosic ester material. The sur- 4 face of this base maybe formed to provide the desired surface-upon the gelatin film formed thereon. It may, for-example, be

so "perfectly smo0t-h or1may present a design of any-desired character, such as a repetition I of a representation of a trade-mark, or for scientific uses, a replica ofa diffraction grating, or the like. The base 5 may suitably 1322. Serial No. 562,726.

be led through feed 'rollers 7 to a"suitable '55 film-applying device, which may be of any desired construction. In the form illustrated, it is diagrammatically shown as a container 8 for the gelatin solution, in which is mounted a rotating roller 9, mounted partly below and partly above the surface of the solution in container 8. Directly above the film-applying roller 9 is mounted a sup-. porting roller 10, which may bearup-on the roller 9 with any desired, variable pressure. The base film 5 passes between the film-v applying roller 9. and the supporting roller 10, and is given a smooth, even coating of the gelatin solution by the roller 9. The base material 5 then passes upward over a roller 11, and thence may be carried between moderately heated radiators 12, 12 to a festoon dryer, indicated at 13. After passing the fllm-applying device, the flexible base 5 carries with it the coating of gelatinous material, indicatedflby the numeral 145, and this coating gradually dries and'hardens upon the surface of the base 5, forming a dense, hardened film. After passing through the festooning device, the gelatin .film 14 is stripped from the flexible base, the latter being formed into a roll 15 and the gelatin film being formed into a roll 16.

The gelatin solution applied for the formationof the film may suitably be one containing a hardening agent. For example, an aqueous solution containing say from '10 to 15% of gelatin and from A, to 2% of commercial (40%) formaldehyde may be employed. From 5 to 8% alcohol may be added to increase the fluidity of the solution and accelerate its drying, and suitable softening agents and preservatives may be in-' cluded. For example, from to 2% of glycerine may be used as a softening agent and from to 2% of phenol as a preservative. Other softening agents, such as sulfonated castor oil, magnesium chloride, cal- V base of the formed and hardened in with the gelatin in the gelatin solution, it is readily apparent that the hardening agent may be supplied by a separate treatment, the gelatin coated base being subsequently carried through a solution of the hardening agent, which may be, for example, a 4 to 6% of formaldehyde, or through its vapor.

In the drying of the gelatin film upon a character described, it is found that the adhesion of the gelatin to the base is so great that the contraction due to drying and to hardening can take place substantially only in the thickness of the film with the result that the film formed is dense and firm. In its contraction, it reproduces .perfectly any marks or impressions formed in the base, so that the film may be given any desired surface pattern.

Although the invention has been described in connection with a band or ribbon of the base material, it is readily apparent that it may be formed as a continuous belt, upon the surface of which the film of gelatin is the same manner as above described. The specific details of apparatus and process above set forth are not intended to be regarded as limitations upon the scope of the so far as included in the accompanying claims.

The base material may likewise be formed invention, except in.

as a surface coating upon a fabric or cellulose material, as is readily apparent.

I claim: 7

1. The method of forming a gelatin film which comprises continuously applyin a coating of gelatin solution to the sur fiace of a traveling cellulose-ester plastic base, supplying a hardening agent in said coating. drying the coating while adhering to the traveling base and stripping the dried coating therefrom as acontinuous dense, coherent film.

2. The method of forming agelatin film which comprises applying a coating of a gelatin solution to the surface of a traveling band of cellulose-ester plastic material, supplying a hardening agent therein, drying the coating while adhering to the traveling band and stripping the dried coating therefrom as a continuous, dense coherent film.

3. The method of forming a gelatin film ,which comprises impressing a superficial (lesign upon the surface of a cellulose-ester plastic base, applying a coating of gelatin solution to said surface, supplying a hardeningagent in said coating, drying the coating while adhering to the base and stripping the dried coating therefrom as a dense, coherent film reproducing the design impressed upon the base.

WILLIAM H OSKINS. 

